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Do Predator Exclusion, Position, And Plant Architecture Influence Hydrilla-Dwelling Macroinvertebrate Communities?, Jonathan C. Fisher Jan 2005

Do Predator Exclusion, Position, And Plant Architecture Influence Hydrilla-Dwelling Macroinvertebrate Communities?, Jonathan C. Fisher

LSU Master's Theses

Hydrilla verticillata invaded south central Louisiana during the 1970s subsequently becoming the dominant submerged macrophyte in floodplain habitats of the Atchafalaya River Basin. The effects of hydrilla on littoral habitat structure, water quality, fish, and macroinvertebrates have been pervasive, and I hypothesized that dense hydrilla stands would also impact vertebrate predation on resident macroinvertebrates, although predation effects would likely be mediated by bed position. During 2003 and 2004, I conducted exclosure experiments in the Atchafalaya River Basin with artificial substrates to test for variations in hydrilla bed macroinvertebrate communities caused by predation, plant architecture, and bed position. To determine invertebrates …

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A Parallel Computing-Visualization Framework For Polycrystalline Minerals, Venkatasrirama Pavankumar Yerraguntla Jan 2005

A Parallel Computing-Visualization Framework For Polycrystalline Minerals, Venkatasrirama Pavankumar Yerraguntla

LSU Master's Theses

In this report, we have reported some preliminary results in the development of a parallel computing-visualization framework for large-scale molecular dynamics simulations of polycrystals of minerals, which are geophysically relevant for Earth’s mantle. First, we have generated the input configurations of atoms belonging to various grains distributed in the space in a way, which resembles the polycrystalline structure of the minerals. The Input configuration is developed using Voronoi geometry. Thus generated polycrystalline system is simulated using the PolyCrystal Molecular Dynamics algorithm. Performance tests conducted using up to 256 processors and a couple of millions of atoms have shown that the …

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Image Processing Techniques To Identify Predatory Birds In Aquacultural Settings, Uma Devi Nadimpalli Jan 2005

Image Processing Techniques To Identify Predatory Birds In Aquacultural Settings, Uma Devi Nadimpalli

LSU Master's Theses

Bird predation is a major problem in aquaculture. A novel method for dispersing birds is the use of a vehicle that can sense and chase birds. Image recognition software can improve their efficiency in chasing birds. Three recognition techniques were tested to identify birds 1) image morphology 2) artificial neural networks, and 3) template matching have been tested. A study was conducted on three species of birds 1) pelicans, 2) egrets, and 3) cormorants. Images were divided into 3 types 1) Type 1, 2) Type 2, and 3) Type 3 depending upon difficulty to separate from the others in the …

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Target Tracking In Wireless Sensor Networks, Tarun Anand Malik Jan 2005

Target Tracking In Wireless Sensor Networks, Tarun Anand Malik

LSU Master's Theses

The problem being tackled here relates to the problem of target tracking in wireless sensor networks. It is a specific problem in localization. Localization primarily refers to the detection of spatial coordinates of a node or an object. Target tracking deals with finding spatial coordinates of a moving object and being able to track its movements. In the tracking scheme illustrated, sensors are deployed in a triangular fashion in a hexagonal mesh such that the hexagon is divided into a number of equilateral triangles. The technique used for detection is the trilateration technique in which intersection of three circles is …

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Development And Model Formulation Of Scalable Carbon Nanotube Processes: Hipco And Comocat Process Models, Adedeji Ebenezer Agboola Jan 2005

Development And Model Formulation Of Scalable Carbon Nanotube Processes: Hipco And Comocat Process Models, Adedeji Ebenezer Agboola

LSU Master's Theses

Carbon nanotubes are seamless cylindrical tubes, consisting of carbon atoms arranged in a regular hexagonal structure. It is considered as the ultimate engineering material because of its unique and distinct electronic, mechanical and material characteristics. The discovery of these materials pioneered the nanotechnology revolution, which encompasses a broad and multidisciplinary spectrum, including nanomaterials, nanobiotechnology, and nanoelectronics. Hundreds of published articles of laboratory scale and pilot plant processes were reviewed that describe potential synthesis and post–synthesis purification methods for large scale production of carbon nanotubes. The main production technologies include electric arc discharge, laser vaporization, and catalytic chemical vapor deposition. These …

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Environmental Factors Influencing Incubation Constancy And Recess Frequency In Gadwall (Anas Strepera) In The Prairie Pothole Region Of North Dakota, Nicole F. Lorenz Jan 2005

Environmental Factors Influencing Incubation Constancy And Recess Frequency In Gadwall (Anas Strepera) In The Prairie Pothole Region Of North Dakota, Nicole F. Lorenz

LSU Master's Theses

I examined nest attendance patterns for 132 Gadwall (Anas strepera) females breeding in the prairie pothole region located in Towner County, North Dakota from May to July 2000 - 2001. Overall, Gadwall had a daily incubation constancy of 76.5 ± 10.8%, and daily recess frequency of 2.2 ± 1.1 with each recess lasting 179.8 ± 133.8 minutes. Unlike other waterfowl species, Gadwall increased incubation constancy and decreased recess frequency as daily high temperature increased and showed no change in constancy with precipitation. Gadwall incubation constancy did not fit the body-size hypothesis, as Gadwall have a lower incubation constancy compared to …

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Behavior Of Heat Straightened Plates Bent Along The Minor Axis, Manish Sharma Jan 2005

Behavior Of Heat Straightened Plates Bent Along The Minor Axis, Manish Sharma

LSU Master's Theses

The heat straightening method of repair for damaged steel structures has been employed for many years. The method was based on the experience of practitioners. Recent research has given an engineering background for the technique and established certain procedures and guidelines to be followed while using heat straightening. Although a scientific basis has now been established, there still exist some major gaps in the data. Misuse of the heat straightening technique has produced fractures in the steel during repair.There are two parameters that may be keys to limiting fracture sensitivity: degree of damage and application of jacking force stress during …

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Hierarchical Indexing For Region Based Image Retrieval, Eka Aulia Jan 2005

Hierarchical Indexing For Region Based Image Retrieval, Eka Aulia

LSU Master's Theses

Region-based image retrieval system has been an active research area. In this study we developed an improved region-based image retrieval system. The system applies image segmentation to divide an image into discrete regions, which if the segmentation is ideal, correspond to objects. The focus of this research is to improve the capture of regions so as to enhance indexing and retrieval performance and also to provide a better similarity distance computation. During image segmentation, we developed a modified k-means clustering algorithm for image retrieval where hierarchical clustering algorithm is used to generate the initial number of clusters and the cluster …

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Fuzzifying [Sic] Markov Decision Process, Ahmed Syed Irshad Jan 2005

Fuzzifying [Sic] Markov Decision Process, Ahmed Syed Irshad

LSU Master's Theses

Markov decision processes have become an indispensable tool in applications as diverse as equipment maintenance, manufacturing systems, inventory control, queuing networks and investment analysis. Typically we have a controlled Markov chain on a suitable state space in which transitional probabilities depend on the policy (or decision maker) which comes from a set of possible actions. The main problem of interest would be to find an optimal policy that minimizes the associated cost. Linear Programming has been widely used to find the optimal Markov decision policy. It requires solutions of large systems of simultaneous linear equations. By the fact that the …

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Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau Jan 2005

Influences On The Establishment Of County Wildfire Risk Mitigation: The Case Of California's Fire Safe Councils, Timothy Richard Soileau

LSU Master's Theses

In response to increased annual wildfire destruction and insufficient wildfire mitigation approaches from the federal government, the state of California adopted Public Resources Code Sections 4290 and 4291 in the year 1991. These laws force the removal of fire-causing agents from public and private areas, and establish what is known as defensible space. Defensible space is defined in Section 4291 as the area within the perimeter of a parcel, development, neighborhood, or community where basic wildland fire protection practices and measures are implemented, providing the key point of defense from an approaching wildfire or escaping structure fire. One method to …

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Improved Watermarking Scheme Using Decimal Sequences, Naveed Shaik Ashfaq Jan 2005

Improved Watermarking Scheme Using Decimal Sequences, Naveed Shaik Ashfaq

LSU Master's Theses

This thesis improves upon the work carried out by Mandhani on decimal sequence watermarking showing that the embedding and decoding algorithms used by Mandhani are not robust. We next specify improvements to these algorithms so that the peak signal to noise ratio (PSNR) is maximized and the distortion introduced in the image due to the embedding is minimized. By exploiting the cross correlation property of decimal sequences, the concept of embedding more than one watermark in the same cover image has been investigated. A comparison between the PSNRs for decimal sequence watermarking and other pseudorandom sequences has been made.

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Autonomic Nervous System Modulation Of The Heart Following A High Carbohydrate Liquid Meal, Calynn Davis Bunol Jan 2005

Autonomic Nervous System Modulation Of The Heart Following A High Carbohydrate Liquid Meal, Calynn Davis Bunol

LSU Master's Theses

The involvement of the sympathetic nervous system in the pathology of obesity has long been a debate among researchers. Various methods of capturing the resting sympathetic activity as well as the response of the sympathetic activity elicited by the introduction of a meal or a bout of exercise in both lean and obese individuals have been investigated. This study examined the autonomic modulation of the heart following a high carbohydrate liquid meal in various body types. Twenty-five females with body mass indexes [weight (kg)/height2(m)] ranging from 19.3-39.5 were grouped according to relative basal energy expenditure adjusted for lean …

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Scalable Schemes Against Distributed Denial Of Service Attacks, Kishori Nanduri Jan 2005

Scalable Schemes Against Distributed Denial Of Service Attacks, Kishori Nanduri

LSU Master's Theses

Defense against Distributed Denial of Service (DDoS) attacks is one of the primary concerns on the Internet today. DDoS attacks are difficult to prevent because of the open, interconnected nature of the Internet and its underlying protocols, which can be used in several ways to deny service. Attackers hide their identity by using third parties such as private chat channels on IRC (Internet Relay Chat). They also insert false return IP address, spoofing, in a packet which makes it difficult for the victim to determine the packet's origin. We propose three novel and realistic traceback mechanisms which offer many advantages …

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Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov Jan 2005

Stability Of Stochastic Pricing Models Under Volatility Fluctuations, Krassimir Zhivkov Nikolov

LSU Master's Theses

The standard theory of the stochastic models used to value financial derivatives contracts involves models whose input parameters are deterministic functions and often constants. Because of the random nature of the changes in the market prices of the financial instruments, the coefficients of these models are inevitably susceptible to random perturbation from their initial estimates. In this paper we will investigate the behavior of some of the most widely used models when small changes are applied to their volatility component. Starting with the Black-Scholes model for the price of a European call option, we will continue our analysis of the …

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Petite Women: Fit And Body Shape Analysis, Lisa Barona Mcroberts Jan 2005

Petite Women: Fit And Body Shape Analysis, Lisa Barona Mcroberts

LSU Master's Theses

Only small quantities of apparel are available to the domestic petite sector, and they do not fit well due to lack of attention to proportion. In addition, other factors contributing to improper fit are a sizing system based on outdated anthropometric data gathered in the 1930s to create the voluntary product standard PS 42-70, and a rising obesity problem, resulting in an array of figure type variations ranging from apple-shaped to pear-shaped women, as opposed to the industry focused hourglass shape. The purpose of this exploratory study was to investigate fit and design with figure type variations for petite women, …

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A Bioeconomic Supply Model For Louisiana Nutria And Impacts On Wetlands Conservation Associated With Economic Incentives, Cheikhna Ould Dedah Jan 2005

A Bioeconomic Supply Model For Louisiana Nutria And Impacts On Wetlands Conservation Associated With Economic Incentives, Cheikhna Ould Dedah

LSU Master's Theses

Nutria (Mayocastor) were first introduced to Louisiana in 1938. With few natural predators and high prolific productivity, they became well established in the surrounding coastal marsh within a few years. Prior to 1980’s, as a result of high demand for nutria products from European countries, harvest pressure was sufficient to keep the population in ‘check’ with their wetlands capacity. By the mid-1980’s, however, prices had fallen sharply, culminating in declining annual harvests and an increasing population. Because of their feeding habits, the increased nutria population has resulted in a substantial amount of wetland degradation. In this thesis, a long-run bioeconomic …

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Roc Comparison Of Acquisition Parameters For Two Pet/Ct Scanners Based On Lesion Detectability In A Torso Phantom, Kenneth Bernstein Jan 2005

Roc Comparison Of Acquisition Parameters For Two Pet/Ct Scanners Based On Lesion Detectability In A Torso Phantom, Kenneth Bernstein

LSU Master's Theses

Positron emission tomography (PET) and computed tomography (CT) are well established and powerful tools for medical diagnostics but even integrated PET/CT scanner images still lack the necessary quality and resolution that would make medical diagnoses flawless. In this thesis experiments were performed to statistically determine the effect that image acquisition parameters have upon diagnostic accuracy. Images from different PET/CT scanners were assessed by comparing subject human diagnostic accuracy from a sample of both professional and student volunteers. The assessment results were compared to the objective NEMA-standards performance data provided by the manufacturers for each scanner. The data analysis method is …

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Thermo And Kinetic Studies On The Sorption And Desorption Of Hydrophobic Organic Contaminants In Sediments, Yunzhou Chai Jan 2005

Thermo And Kinetic Studies On The Sorption And Desorption Of Hydrophobic Organic Contaminants In Sediments, Yunzhou Chai

LSU Doctoral Dissertations

This study investigated the correlation of desorption resistance of hydrophobic organic contaminants (HOCs) in sediment and the heterogeneity of sediment organic matter (SOM). The amorphous and condensed phase organic carbon contents were defined by the method of Gustafsson et al. (1997) using thermal oxidation of sediment under 375°C. The desorption-resistant fraction of contaminants in sediments was operationally defined as the fraction that could not be removed by the adsorbent XAD-2. The correlation of the desorption-resistant fraction with sediment organic carbon characteristics was evaluated for both laboratory-inoculated and field-contaminated sediments. No strong correlation between the desorption resistant fraction in laboratory-inoculated sediments …

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Graphical Pilot Interface Simulator (Gpis), Jeffry Jorge Handal Jan 2005

Graphical Pilot Interface Simulator (Gpis), Jeffry Jorge Handal

LSU Master's Theses

The thesis develops a graphic interface for a dynamic system simulation implemented in the SIMULINK environment. The dynamic system is a B747-200 modeled as a rigid body with six degrees of freedom. The equations and database of aerodynamic coefficients over the complete flight envelope were provided by NASA’s Langley Research Center for the research project “Aircraft Safety: Managing Control Upsets.” The purpose of the interface is to allow the user to “fly the plane from the keyboard;” i.e., interact with the simulation by manipulating, from the keyboard, the main control surfaces and engine thrust and observing the performance of the …

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Blind Multiridge Detection And Reconstruction Using Ultrasonic Signals, Rekha Katragadda Jan 2005

Blind Multiridge Detection And Reconstruction Using Ultrasonic Signals, Rekha Katragadda

LSU Master's Theses

Time-frequency signal analysis has been widely applied in the modern radar, acoustic, sonar and ultrasonic signal processing techniques. Recently, the nondestructive testing (NDT) techniques via the ultrasonic instrumentation have shown the striking capability of the quality control for the material fabrication industry. In this thesis, we first provide a general mathematical model for the ultrasonic signals collected by pulse-echo sensors and then design a totally blind, novel, signal processing NDT technique relying on neither a priori signal information nor any manual effort. The signature signal can be blindly extracted by using the automatic optimal frame size selection for further modeling …

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Analysis Of Performance Of Single-Phase Reluctance Linear Motor, Subhadra Devi Ganti Jan 2005

Analysis Of Performance Of Single-Phase Reluctance Linear Motor, Subhadra Devi Ganti

LSU Master's Theses

The design and principle of operation, as well as the electromechanical phenomena of a single-phase linear reluctance motor are discussed. The motor with transverse magnetic flux consists of a primary part, which is moving and a secondary part which is stationary and does not have any windings. The motor can operate under AC or DC supply. When supplied from an AC source it must be equipped with a capacitor connected in series with the coil. In this case the motor operates on the basis of resonance in an RLC primary circuit. When supplied from a DC source it must be …

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Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher Jan 2005

Modern Interpretation Of Euclid's Theory Of Ratio And Proportion, Mark Robert Stecher

LSU Master's Theses

Euclid’s Elements is the foundation for geometry. Book V of Euclid’s Elements, which is independent from the earlier books, focuses on multiples, ratios, and proportions. This paper presents a model of the conceptual content of Book V, but using carefully selected modern notation to represent Euclid’s ideas without changing them drastically. All of the propositions and proofs from Euclid have been restated using just enough modern language to make clear for a modern reader. We also present a modern theory that bears analogy, proposition by proposition, to Euclid’s theory, but uses rigorous modern methods of proof.

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Patterns Of Self-Expression And Impression Management In Blogs, Ana Keshelashvili Jan 2005

Patterns Of Self-Expression And Impression Management In Blogs, Ana Keshelashvili

LSU Master's Theses

The constant process of technology development offers Internet users new tools, allowing them to enjoy their right of free expression. One of the latest popular tools introduced for use by mass audience on the Internet is a weblog (or blog). There are more than 4.12 million blogs on the Internet maintained by different people with different purposes. Some of the bloggers manage to create an image that makes them "celebrities" among the community of bloggers. These are the people whose blogs are among the most well-known and also regularly linked by other bloggers. Besides, media's view of blogging comes directly …

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The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker Jan 2005

The Effects Of Aluminum Concentration On Growth Responses In Six Spartina Alterniflora Genotypes, Daniel Farrell Becker

LSU Master's Theses

Elevated soluble aluminum concentrations can adversely affect plant growth. During a drought, wetland soils may experience higher than normal soluble aluminum due to the oxidation of metal sulfides and resulting decreases in pH, which mobilizes metallic cations. Louisiana coastal salt marshes were subject to a record-setting drought in the winter and spring of 2000 which was coincident with the die-off of large expanses of salt marsh, termed " brown marsh ". Spartina alterniflora was the primary plant species affected. However, because some individuals within large areas of die-off survived the brown marsh event, they may have been the more resistant …

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Effect Of Multiuser Interference On Subscriber Location In Cdma Networks, Rohit Sharma Jan 2005

Effect Of Multiuser Interference On Subscriber Location In Cdma Networks, Rohit Sharma

LSU Master's Theses

The last few years have witnessed an ever growing interest in the field of mobile location systems for cellular systems. The motivation is the series of regulations passed by Federal Communications Commission, requiring that wireless service providers support a mobile telephone callback feature and cell site location mechanism. A further application of the location technology is in the rapidly emerging field of intelligent transportation systems, which are intended to enhance highway safety, location based billing etc. Many of the existing location technologies use GPS and its derivatives which require a specialized subscriber equipment. This is not feasible for popular use, …

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A Crisis Of Opportunity: The Example Of New Orleans And Public Education In Antebellum Louisiana, Sarah Elisabeth Lipscomb Jan 2005

A Crisis Of Opportunity: The Example Of New Orleans And Public Education In Antebellum Louisiana, Sarah Elisabeth Lipscomb

LSU Master's Theses

The purpose of this study is to explore the development of public education in antebellum Louisiana. Using primarily public records, I found that despite the successful system instituted in New Orleans in the early 1840s, the rest of Louisiana faltered in its attempts to establish free public schools. Notwithstanding the requirement contained in the 1845 Constitution that each parish must organize public schools, the lack of guidance, supervision, and funding from the state legislature all coalesced to condemn public education in most of the rest of the state. As public schools in New Orleans thrived throughout the decades leading up …

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Riding Out The Risks: An Ethnographic Study Of Risk Perceptions In A South Louisiana Bayou Community, Susan Camille Manning Jan 2005

Riding Out The Risks: An Ethnographic Study Of Risk Perceptions In A South Louisiana Bayou Community, Susan Camille Manning

LSU Master's Theses

This ethnographic study explores the risk perceptions of a small unincorporated coastal community in southeastern Louisiana. This community has experienced social and environmental change due to events including tropical storms and hurricanes, erosion, subsidence, oil and gas activities, development, and the impact of global seafood markets. Many global risk perception studies have focused on the perception of risk to human health and property connected with natural and technological disasters, but few have explored the issue of minorities and small at-risk communities. To explore this theoretical and methodological gap, this study uses a variety of qualitative ethnographic methods to examine a …

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An Application Of Parallel Computation To Collaborative Optimization, Shahab Nayyer Jan 2005

An Application Of Parallel Computation To Collaborative Optimization, Shahab Nayyer

LSU Master's Theses

Multidisciplinary Design Optimization (MDO) has evolved as a discipline which provides a body of methods and techniques to assist engineers in solving large scale design problems. There are many frameworks for formulating MDO problems. These frameworks can be broadly classified as single-level or bi-level formulations. Collaborative Optimization (CO) is one of the popular bi-level formulations to solve an MDO problem. There are numerous design optimization problems which are highly CPU time intensive and require a long simulation time. With the advent of cheaper and faster available PC’s, distributed parallel computer clusters have become very popular. These clusters provide large computing …

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Comparative Study Of The Physical And Mechanistic Properties Of Hma Mixture: Field Vs Laboratory, Chenggang Zhang Jan 2005

Comparative Study Of The Physical And Mechanistic Properties Of Hma Mixture: Field Vs Laboratory, Chenggang Zhang

LSU Master's Theses

The objectives of this study were to investigate the variability in the physical and mechanistic properties of HMA due to production, characterize and compare the mechanistic properties of roadway cores and laboratory compacted samples, develop the relationship between modulus from in situ NDT and those obtained from laboratory tests on roadway cores, and compare air voids measurements between laboratory and field test methods. Six ongoing rehabilitation projects in Louisiana were selected, in each of which several test sections were tested. Comparative analyses were conducted on density measurements between two laboratory (AASHTO T-166 and ASTM D6752-02, or Vacuum sealing) and one …

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Energy-Rate Based Mac Protocol For Wireless Sensor Networks And Key Pre-Distribution Schemes, Ramaraju Kalidindi Jan 2005

Energy-Rate Based Mac Protocol For Wireless Sensor Networks And Key Pre-Distribution Schemes, Ramaraju Kalidindi

LSU Master's Theses

Sensor networks are typically unattended because of their deployment in hazardous, hostile or remote environments. This makes the problem of conserving energy at individual sensor nodes challenging. S-MAC and PAMAS are two MAC protocols which periodically put nodes (selected at random) to sleep in order to achieve energy savings. Unlike these protocols, we propose an approach in which node duty cycles (i.e sleep and wake schedules) are based on their criticality. A distributed algorithm is used to find sets of winners and losers, who are then assigned appropriate slots in our TDMA based MAC protocol. We introduce the concept of …

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